Alphabeta Math

Induced Subgraphs and Hereditary Graph Classes — Examples

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✓ 12 results · all verified · 0 also independently AI-judged
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1 · Prerequisites
2 · Logical flowchart

3 · Items

Counterexample

K₃ contains P₃ as a subgraph but not as an induced subgraph

Example

ind_K₂(G)=2|E(G)| under the induced-embedding convention

Example

Complete graphs form the hereditary class with forbidden basis {K̄₂}

Example

Edgeless graphs form the hereditary class with forbidden basis {K₂}

Example

A graph is P₃-free if and only if every connected component is complete

Counterexample

The class of connected graphs is not hereditary

Counterexample

The class of regular graphs is not hereditary

Example

P₄ is both connected and anticonnected

Example

Complete, anticomplete and mixed vertex-set pairs in P₄

False statement

Every hereditary graph class has a finite forbidden induced-subgraph basis

False statement

Every hereditary graph class is closed under taking arbitrary subgraphs

Example

Complementary hereditary classes have complementary forbidden bases

Sources